Add static libraries *.jar to Android.mk based build

in Android.mk

LOCAL_STATIC_JAVA_LIBRARIES := mylocaljar

LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES := mylocaljar: mylocaljar.jar

mylocaljar.jar should be in root directory of the project. Look at the Calculator app's Android.mk in Android tree as an example

Fragments for All

http://android-developers.blogspot.com/2011/03/fragments-for-all.html

Automatic thread

Nice piece of code from Android e-mail client

public static AsyncTask runAsync(final Runnable r) 
{  return new AsyncTask() {
       @Override 
       protected Void doInBackground(Void... params) {
            r.run();
            return null;
       }}.execute();
    }
    runAsync(new Runnable() {
      @Override
      public void run() {}}
    );

Copy entire directory tree in Linux

cp -r srcdir destdir

Grep search

grep -i -n -r 'my search term' --include=*.java .

searches for 'my search term' in current directory and sub directories in all files